Damping in Fusion 360

[Anonymous]

Hi,

I am doing some event simulations using Fusion 360, however I have some questions regarding damping. Within the "settings" tab, under "damping" there is only one checkbox for "Rayleigh damping", hence my questions are:

1. If I do not select this box, will the system assign damping based on damping coefficient input within the materials properties input form?

2. If positive, why Fusion does not accept damping coefficients less than 0.01? According to literature, materials such as brass have damping ratio of 0.009, and aluminum goes around 0.0035. I am assuming that this value  for "damping coefficient" is equivalent to "damping ratio"

3. Or, is Rayleigh damping the only alternative in Fusion 360? 

Thank you,

Manuel Umanzor

[tomasz.kasperek · Accepted solution]

Hi @Anonymous,

To activate damping you have to mark checkbox Settings -> Damping -> Rayleigh Damping. 

Fusion accepts damping coefficients less than 0.01 within the material properties, but there is a limitation of entering decimal places (less than 3). So you can set 0 or next 0.01. I reported this issue to Development Team. 

Regards

[Anonymous]

Hello Tomasz,

Thanks a lot for your reply. So, Rayleigh damping is the only alternative in Fusion, correct? There is not such a thing as plugging in the dominant frequency and damping ratio like in Nastran?

Best regards,

Manuel